Yingjie Lin , Yanxin Liu , Yufeng Song , Zhixiang Deng , Zhenhong Wang , Jun Liu , Chunxiang Zhang , Pinghua Tang
{"title":"Pulsating pure-quartic solitons with spectral asymmetry in an ultrafast fiber laser","authors":"Yingjie Lin , Yanxin Liu , Yufeng Song , Zhixiang Deng , Zhenhong Wang , Jun Liu , Chunxiang Zhang , Pinghua Tang","doi":"10.1016/j.chaos.2025.117169","DOIUrl":"10.1016/j.chaos.2025.117169","url":null,"abstract":"<div><div>In this work, we report the first experimental generation and observation of pure-quartic soliton (PQS) pulsations with spectral asymmetry in an ultrafast fiber laser. In addition to the asymmetric spectral sidebands, a unique feature of these observed pulsating PQSs lies in that the pulsation periods are fairly stable for varying net fourth-order dispersion (FOD) values and pump powers. Moreover, the pulsating PQSs exhibit a maximum average output power of ~22.16 mW, corresponding to a pulse energy of ~2.34 nJ. Finally, numerical simulations have been performed, which are in good agreement with the experimental results. These findings not only reveal a new dynamic regime of PQSs but also provide critical insights into the underlying mechanisms governing their formation and stability, further laying a foundational framework for the future development of high-energy PQS fiber lasers and contributing to a broader understanding of soliton dynamics driven by higher-order dispersion effects.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"200 ","pages":"Article 117169"},"PeriodicalIF":5.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144987940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Stokes-Brinkman equations with diffusion and convection in thin tube structures","authors":"Antonio Gaudiello , Grigory Panasenko","doi":"10.1016/j.jde.2025.113728","DOIUrl":"10.1016/j.jde.2025.113728","url":null,"abstract":"<div><div>The steady state Stokes-Brinkman equations coupled with a system of diffusion-convection equations in a thin tube structure is considered. The Brinkman term differs from zero only in small balls near the ends of the tubes. The boundary conditions are: given pressure and concentrations at the inflow and outflow of the tube structure, the no slip boundary condition on the lateral boundary for the fluid, and Neumann type condition on the lateral boundary for the diffusion-convection equations. In this paper, the existence, uniqueness, and stability of the solution to such a problem are proved. Moreover, some <em>a priori</em> norm-estimates depending on the small thickness of the tubes are also provided. This model is well suited to describing thrombosis in blood vessels.</div></div>","PeriodicalId":15623,"journal":{"name":"Journal of Differential Equations","volume":"450 ","pages":"Article 113728"},"PeriodicalIF":2.3,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144933089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The right-sided quaternionic free metaplectic transformation and associated uncertainty principles","authors":"Khaled Hleili, Youssef El Haoui","doi":"10.1007/s13324-025-01125-y","DOIUrl":"10.1007/s13324-025-01125-y","url":null,"abstract":"<div><p>The aim of this paper is to investigate the right-sided quaternionic free metaplectic transformation (QFMT) and its associated uncertainty principles (UPs) for <span>(mathbb {R}^{2d})</span>-dimensional quaternionic-valued signals. First, we establish the fundamental mathematical properties of the QFMT, including partial derivatives, the inversion formula, Parseval’s theorem, and the Hausdorff–Young inequality. Next, we establish various UPs within this framework, such as the Rènyi and Shannon entropy UPs and Donoho–Stark’s UP in terms of concentration. Finally, we derive <span>(L^a)</span>-bandlimited variant of the Donoho–Stark UP in the QFMT domain.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"15 5","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144934578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dichotomy laws for the Hausdorff measure of shrinking target sets in \u0000 \u0000 β\u0000 $beta$\u0000 -dynamical systems","authors":"Yubin He","doi":"10.1112/jlms.70284","DOIUrl":"https://doi.org/10.1112/jlms.70284","url":null,"abstract":"<p>In this paper, we investigate the Hausdorff measure of shrinking target sets in <span></span><math>\u0000 <semantics>\u0000 <mi>β</mi>\u0000 <annotation>$beta$</annotation>\u0000 </semantics></math>-dynamical systems. These sets are dynamically defined in analogy to the classical theory of weighted and multiplicative Diophantine approximation. While the Lebesgue measure and Hausdorff dimension theories for these sets are well-understood, much remains unknown about the Hausdorff measure theory. We show that the Hausdorff measure of these sets is either zero or full depending upon the convergence or divergence of a certain series, thus providing a rather complete measure theoretic description of these sets.</p>","PeriodicalId":49989,"journal":{"name":"Journal of the London Mathematical Society-Second Series","volume":"112 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144934813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}